Free King of the World by Celia Fremlin

theory he may be working on – something far, far beyond your intellectual scope – and mine too, of course, but at least I have the sense to recognise my limitations.”
    At this Norah – braver in those early days than she could possibly dare to be now – stood her ground.
    “It isn’t a mathematical theory he’s working on,” she insisted. “I told you – it’s the seventeen-times table, going on and on and on. There can’t be any sense in it – especially since he’s got that super-expensive calculator you bought him. If he wants to know what seventeen-times-something is, all he has to do is …
    Expression had come over Mervyn’s features at last. She was aware of a mounting tension in him, overlaid with a veneer of withering scorn.
    “A typical Norah-ism!” he sneered – and she could tell that he was struggling to convince himself as well as her. “You haven’t the faintest idea of what a calculator can and can’t do, and yet you have the nerve to make these judgements! Calculators don’t extend to infinity, you know; Christopher’s onto something important there, because actually there’s no such thing as infinity, it’s just a mathematical abstraction.”
    She realised clearly enough that, deep down, he was as scared as she was by Christopher’s aberration; but now, suddenly, his face cleared. He had thought of something.
    “Hasn’t it occurred to you,” he exclaimed, “That seventeen is a prime number? Research into the nature of prime numbers is something that has engaged the minds of top mathematicians for centuries. Obviously, that’s what Christopher is working on. It may be – I’m sure it will be – that our son is destined to be the genius who will finally solve the problem.”
    Mervyn turned back to his work with an air of overwhelming relief, and the uneasy exchange was over. The problem of prime numbers – whatever it might consist of– was serving as a comfortable substitute preoccupation for the problem of Christopher’s mental state.
    And thus it remained for the following weeks, during which Norah’s anxieties slowly and steadily deepened.

Chapter 8
    By the time Norah had finished her phone call, relieved rather than dismayed by what she had heard – centipedes which tapped out Morse signals with their hundred legs were a soft option compared with the thing she had feared – it was quite dark. She drew the heavy, floor-length curtains against the misty darkness outside, and then sat for a while, considering her next move. They didn’t seem to be thinking of throwing her out – not just yet, anyway; though it was awkward that they weren’t letting her pay any rent. It made things embarrassing which would otherwise have been easy and straight-forward. For instance, right now she was wondering if she was entitled to switch on the imitation coal fire in this apparently communal living-room. Must have a talk with Diana when she comes in, she mused; and even as the thought passed through her mind, it was borne in upon her that Diana was already in, was, at this very moment, coming into the room.
    But how strangely she was behaving! Pushing the door a little way open, and peering cautiously round it, as if fearing that something might be about to leap out on her.
    “Hullo!” Norah said in what she felt to be a perfectly normal voice, and was about to continue with some sortof apology for having used the phone, and a promise to pay for the call, when Diana silently withdrew her head and retreated without a word, closing the door softly behind her.
    It was a couple of uneasy hours later when the two met up in the kitchen, brewing respectively a mug of coffee and a half-pint packet of instant soup. With the to-ing and fro-ing in the restricted space around the cooker, unbroken silence was impossible to maintain; especially for Diana, whose curiosity had by now overcome her initial panic at finding herself locked up (well, sort of) with a raving lunatic, and who longed